Abstract: A subsea arrangement including a main enclosure having a main enclosure volume; at least one main pressure compensator having a variable compensation volume in fluid communication with the main enclosure volume and configured to compensate volume variations of an internal fluid in the main enclosure volume; and at least one pressure sensor arranged to measure a pressure of the internal fluid. A method for detecting a malfunction of a subsea arrangement including a main enclosure having a main enclosure volume and at least one main pressure compensator is also provided.

Abstract: A buoyancy compensation apparatus for underwater use by a SCUBA diver, includes a pressurized air source, a buoyancy vest including air chambers and a pressure regulating unit. The pressure regulating unit includes a chamber in communication with the vest air chambers and the pressurized air source. The pressure regulating unit also includes a normally closed air injection valve and a normally closed relief valve. The wall of the pressure regulating unit chamber includes a flexible portion that flexes inwardly when outside water pressure exceeds the pressure in the vest air chambers, which, in turn, opens the air injection valve. The relief valve opens when air pressure in the vest air chambers exceeds outside water pressure. The air injection and relief valves respond faster than the walls of the buoyancy vest air chambers so that the volume of the vest air chambers remain generally constant even as the diver changes depth.

Abstract: A pressure equalizer for an underwater vessel can include a pneumatic reservoir and a pressure compensating valve (PCV). The PCV can be in fluid communication with the surrounding underwater environment and the vessel interior, and in selective fluid communication with the reservoir. The PCV can further include a valve body and a valve plug. As the PCV opens, the plug moves within the body to establish a path of fluid communication from the reservoir, through the PCV to the vessel interior, to allow flow of high pressure compressible fluid from the reservoir into the interior to pressurize the vessel interior. As the vessel interior pressure equalizes with the surrounding environment, the plug moves within the body to close the fluid communication path with the reservoir, thereby stopping the flow of compressible fluid into the vessel interior to maintain the equalized pressure.

Abstract: The present disclosure relates to a device for lifting and lowering a load in water, including a hoisting gear with a first hoisting rope and a storage drum with a second hoisting rope, which preferably are arranged on a floating unit. In accordance with the present disclosure, a hoisting gear frame is fastened to the first hoisting rope, whose buoyancy in water is variably adjustable. Furthermore, the present disclosure relates to a method for lifting and lowering a load in water by using such a device.

Abstract: An electrical power system for stationary or movable subsea loads (7) provides one common feeder for multiple electric motors which can be individually controlled. Operational flexibility and operational safety for operation in varying water depths is provided by encapsulating electrical functional element (6) of a subsea power system with a subsea electrical distribution system (5) individually or in-groups. Electrical functional element (6) and their semi-conductor elements are arranged within at least one fluidized internal pressure casing (13). An external pressure casing (12) is provided for the subsea electrical distribution system (5) and/or other components of the subsea system. A high frequency power transmission to the subsea pressurized distribution system (5) with pressurized semi-conductor components reduces weight and size of subsea transformers (4b) and cables (9) employed in subsea systems (10).

Abstract: An improved buoyancy compensation device having a lesser change in buoyancy with depth than conventional buoyancy compensation devices which use ambient pressure bladders is disclosed. The improved device comprises one or more elastic members that, throughout the working range of diving pressures and volumes, is always elastic and, when pressurized, maintains an internal air pressure that is always greater than the ambient pressure at any dive depth. The invention also relates to a method of providing a buoyancy compensation device with an elastic member having a lift versus depth characteristic that approaches the lift versus depth characteristic of a constant or fixed volume buoyancy compensation device.

Abstract: A floating lowering and lifting device (1) includes a floating structure (2) and a lifting unit (3) lowerable from the floating structure (2) towards the sea bed, the lifting unit (3) having a chamber (5) with at least one gas-inlet opening (9) in its wall (27) and an equalization opening (23, 25) in its wall (27), a gas supply (13) being connected to the gas inlet opening (9) The device includes a control element (15) connected to the gas supply (13) for controlling a gas supply rate to the chamber (5), wherein the chamber (5) includes a releasable coupling member (7) for releasably attaching to a load (8).

Abstract: A pressure regulator for breathing apparatus controlled by a diaphragm, piston or bellows having one face exposed to a reference pressure which is automatically maintained at a level substantially the same as ambient pressure by means of a metering valve communicating with pressure at the regulator outlet and operated by a flexible diaphragm exposed to ambient pressure, and a pressure relief valve to vent excess reference pressure to the outside of the regulator.

Abstract: A method and a device for letting out gas from a life jacket for divers, the device being adapted to be in gas flow communication with an interior of the life jacket. Gas is drawn into the device from the interior of the life jacket, compressed in the device, and discharged from the device to a medium surrounding the device.

Abstract: A buoyancy control device for divers includes a plurality of inflatable members each adapted to be inflated to a predetermined maximum volume, or to be deflated, and a fluid distributor for selecting the inflatable members to be inflated and to be deflated, thereby controlling the buoyancy of the device. The fluid distributor includes a housing having an inlet port connectible to a source of pressurized fluid, a venting port leading to the atmosphere, and a plurality of outlet ports connected to the inflatable members. A flexible membrane overlies a grooved surface in the housing, and a valve member is movable over the membrane to press it into the groove such as to effect the communication between the inlet and venting ports with respect to selected outlet ports.

Abstract: A pressure equalizer for use for storing, generating and dispensing gas from substantially thin walled tanks at great depth beneath the sea has a gas generating tank contains a low-temperature, liquified gas which upon the application of heat generates a high-pressure gas which is stored in a gas storage tank into and out of which sea water freely flows through the bottom. A gas supply line is connected at one end by branches to the tops of the respective tanks and at the other end to a device utilizing gas generated in the gas generating tank.

Abstract: A mobile submersible caisson is employed to drill for and recover petroleum products from subsea wells and to deliver the products to shore or to vessels at the well site. The well drilling technique applies to water depths beyond 300 ft. and in areas where severe winds, waves, spray and frigid atmosphere can cause long downtime or make it impossible to maintain the positions of surface platforms for extended periods of time. Caissons containing drilling, completion, workever, separation, pumping and compressing equipment are towed to sea in the caisson in the horizontal position. At the work site the caisson is erected, connects an attached wire cable to a platform placed on the sea bottom, and is submerged and winched down. The caisson mates and becomes sealed with the platform, providing a one atmosphere working space for the drilling crew. Water between the caisson and the platform is pumped out so this area can also be used as a work area.

Abstract: Disclosed is an improved casing for containing cameras, videocameras, flashlights, portable radios and other articles which can be used in scuba diving. It is designed to cause the inner pressure of the casing to vary and balance with the surrounding water pressure. It is guaranteed free from deformation, collapse or water invasion in underwater use without using thick strong wall or frame structure.

Abstract: A pressure equalizing cabinet for instruments intended to be submerged in water is described. The device includes a source of compressed air and a piston in a cylinder. One side of the piston is in communication with the interior of the cabinet and the other side is in communication with the ambient. The piston also mounts a needle valve at a port in a conduit between this source of compressed air and the cabinet interior. When the pressure in the ambient exceeds the internal pressure, the piston is displaced to admit a flow of compressed air into the cabinet. When the pressure in the cabinet exceeds the ambient the piston closes the valve. A bleed valve is also provided for venting excess pressure within the cabinet during ascent.

Abstract: An actuator usable in a first fluid under a high pressure, e.g. on board a submarine operating at great depths to release or jettison ballast and wherein the first fluid is external to the submarine, comprises a plunger which is mobile by means of a spring and is held in place by a locking member. The plunger, its spring and the locking member are located within a frame which is filled with a second fluid, while a flexible skirt and two deformable sleeves enable the pressure of the second fluid to adapt constantly to that of the first fluid.

Abstract: This invention relates to an apparatus for facilitating working on especially horizontal underwater portions of ship hulls, pontoons and other floating objects. The novel feature resides in that the apparatus comprises a screen structure adapted to be tightly fitted along the edges of the surface on which operations are to be carried out, and projecting downwardly from the surface, the screen structure being sealed against the surface and laterally, but perforated or open downwardly, and a pipe for introducing air with a pressure adapted to the water pressure prevailing at the actual depth, into the space within the screen structure in order to provide an air volume serving as a work-space, under the surface.

Abstract: The ambient pressure of the environment of an individual within a vessel is varied between an upper and lower pressure value by providing the vessel with a mass of gas sufficient to fill at least a substantial part of the vessel, and varying the quantity of liquid, primarily water, in the vessel in order to cause the pressure therein to vary correspondingly between the upper and lower values.

Abstract: A submergible, underwater well completion habitat and a method of employing the same in the completion of wells at extended depths. The well completion habitat may be attached to an underwater well platform and maintained at a pressure of sufficient value to expel water from the work chamber and also to maintain it substantially water free so that one or more saturated divers may work within the chamber to complete the well. This abstract of the invention is neither intended to define the scope of the invention, which, of course, is measured by the claims, nor is it intended to limit the invention in any way.

Abstract: A submarine pipeline alignment rig includes a working section and a detachable truss section having a fixed fulcrum for engagement with a submerged conduit section. The rig also includes a vertically movable housing which provides an encapsulated underwater work space that may be positioned around the exposed end of the submerged conduit section. A manipulator mounted on the housing affects alignment of conduit sections relative to each other by pivoting them about the fixed fulcrum so that adjacent conduit sections can be connected or repaired. Locking devices avoid inadvertent release of conduit sections from the alignment rig and enhance operating safety. Both incremental and continuous vertical adjustments are provided for the locking devices of the fulcrum and the manipulator to accomodate conduits of various nominal sizes.

Abstract: A system for varying specific gravity of a submersible or any immersed obt under a pressurized environment which includes a compressible piston designed to collapse a certain amount proportional to the submersible's depth so that the specific gravity of the submersible or other immersed object varies and remains almost equal to the specific gravity of the surrounding medium such as water.

Abstract: A method and apparatus for increasing the safety and productivity of tunnel workers active in high pressure environments is disclosed. The workers are housed at an intermediate pressure over a "work week" of at least several days and are transported between the tunnel face and the life support chamber in which the workers are housed in a pressurized personnel transport chamber. The housing contains sanitary, sleeping, decompression, storage and dining facilities and is generally located at the tunnel entrance. In the preferred embodiment, the intermediate pressure is about half of the tunnel working pressure but not more than about 20 psig and preferably less than 17 psig. It is expected that a decreased incidence of bone related diseases and bends will result due to the reduced number of full decompressions from the tunnel work environment.

Abstract: A capsule for enclosing a sub-sea installation part is intended to be left water-filled and thus means for sensing oil or gas leaks from the part is disposed in the upper part of the capsule to where such leakage will float.

Abstract: A vessel for working under water comprising a substantially spherical residence chamber with an atmospheric pressure therein and accommodating necessary monitoring apparatus for controlling working tools and devices arranged on the outside of the residence chamber. The working tools and devices are mounted on a service section to which the residence chamber is detachably affixed by a coupling apparatus actuated from the residence chamber. In case the service section with its working tools and devices gets hooked or wedged during the underwater operation the residence chamber can be released from the service section and allowed to rise to the surface separated from the service section. The working tools and devices of the service section are so designed that in any working positions they do not render the escape path of the residence chamber blocked.